Forced applying attachment for portable power drills



July 8, 1958 w, w 2,842,341

I FORCE APPLYING ATTACHMENT FOR PORTABLE POWER DRILLS I Filed June 21, 1955 INVENTOR.

27 28 39 FREDRICK W. WINK ATTORNEYS FORCE APPLYENG ATTACHMENT FGR PORTABLE PUWER DRELLS Fredrick W. Wink, Winnipeg, Manitoba, Canada, assignor of one-half to Each G. Herzherg, Elm Grove, Wis.

Appiication dune 21, 1955, Serial No. 516,870

Claims. (Cl. 255-=-52) supporting a gasoline engine or other motor which through gearing drives a drill shaft, the frame being provided with hand grips for supporting the machine and applying force to the drill bit. When a core is to be taken from concrete, rock and other very hard structure, a tubular diamond drill bit is used, and the cutting operation is very slow since the operator holding the machine can apply only limited pressure on the drill bit.

The principal object of the invention is to provide a simple and practical pressure booster for such a drilling machine so that the cutting operation will be speeded up in drilling in very hard material, the booster device being operated by a second man so that much greater force may be applied to the drill bit.

The invention contemplates a hand lever with an open portion through which the drill shaft extends, one end of the lever being adjustably anchored laterally of the drill hole to the rock formation being drilled, and the opposite sides of the open portion of the lever being flexibly connected to a collar swivelled on the frame of the machine concentric with the axis of the drill shaft so that the additional force may be properly and eifectively applied to the drill bit.

With the above and other objects and advantages in view, the invention resides in the novel combinations and arrangements of parts and the novel features of construction hereinafter described and claimed, and illustrated in the accompanying drawings which show the present preferred embodiment of the invention.

In the drawings:

Fig. 1 is a view showing the invention in use, the attachment being in elevation and most of the drilling ma chine being shown in dotted lines;

Fig. 2 is a detail perspective view of the lever member;

Fig. 3 is a detail side elevation of a portion of Fig. 1 looking in a direction at 90 from that of Fig. 1; and

Fig. 4 is a detail longitudinal sectional view through the drill driving shaft bearing member which is bolted to the gear casing of the drilling machine, the drill shaft and its driving shaft being shown in dotted lines.

Referring more in detail to the drawings, the numeral denotes as a Whole the body or frame of a portable power drill. The frame may have a suitable base 11 by which the machine may be supported when not in use, and above the base is shown a gas engine conventionally represented at 12. Adjustably swiveled at 13 on one side of frame it is a gear housing 14 from one side of which projects a drive shaft 15a to which the drill shaft 15 is attached, the latter forming a continuation of the 2,842,341 Patented July 8, 1958 pic drive shaft. Suitable gearing in the casing 14connects the engine shaftto the drive shaft 15a-to rotate the drill shaft 15 and the swiveled connection permits the drill shaft 15 to be variously positioned with respect to the frame It). The drill shaft 15 and its drive shaft are preferably tubular so that water from a hose connection 16 may be supplied to a tubular diamond drill bit 17 on the shaft or drill 15, or on a detachable extension of the latter. When the machine is in use it is supported by the operator by means of the two loop-like handles '18 and 19, one being carried by the gear casing 14 arid the other by the body frame 10.

Removably fastened to one side of the gear casing 14 is a shaft bearing member 20 through which the drive shaft 15a projects, as shown in Fig. 4. This member 20 has acylindrical hub portion 21 at one end of which is an annular attaching flange 22 removably secured to the easing l t/by bolt 23 disposed in an annular series of holes 23a in'the plate-like flange. Formed in the outer face of the hub'21 is an annular groove 25 to rotatably receive a two-part ring "or collar 26. The two semicircular sections of this swiveled 'collar have opposed radially projecting ends 27 apertured to receive bolts 28.

The pressure applying lever 30 has near one end, as shown in Fig. 2, an open portion through which the drill shaft extends, the other end of the lever serving as a hand grip. This open portion is in the form of an elongated loop and may be diamond shaped as shown, that is, it has two oppositely bowed or angular portions 31. These bowed portions 31 at one end are united at 32 and their opposite ends merge and are united to each other at one end of the handle portion of the lever. The lever is preferably made as shown in Fig. 2 from a piece of tubular metal and at the cnteral points of the oppositely bowed portions 31 are welded loops or eyes 33. These are disposed on one side face of the lever and are adapted to be removably engaged by hooks 34 at the ends of fiat rectangular plates 35. Short chains 39 consisting of few links are connected between the plates 35 and the diametrically opposed bolts 28 which unite the sections of the swiveled collar 26. Welded on the end 32 of the lever on its side opposite the eyes 33 is a laterally projecting hook 37 for coaction with a lever anchoring chain 38. This chain may be suitably fastened to a stationary support so that the chain and hook serve as the fulcrum for the lever. As shown an anchor bolt 40 of the expanding type is set in a hole made in the rock formation being drilled and has an eye or a hook 41 to which the chain is anchored. Any kind of anchor bolt may be used and the one shown is conventionally illustrated as having two opposed wedge-shaped parts on the bolt so that when the device is tightened, those parts move outwardly and grip the wall of the hole. Any of the links of the free portion of the chain may be engaged with the hook 37 so that the lever may be adjusted from time to time as the drilled hole deepens.

It will be seen that when the parts are assembled as shown in Fig. 1, one operator supports the drilling machine by means of the handles while another grasps the handle end of the lever and swings it toward the rock formation R so that greater force may be applied to the drill bit than can be applied by the operator holding the machine. Because of the open portion of the lever and the flexible connections between the same and the diametrically opposed parts of the swiveled collar or ring 26, an even pressure will be applied and there will be no tendency of the drill shaft to be angled. The swiveled mounting of the collar 26 permits the lever to be disposed at various radial angles with respect to the axis of the drill shaft.

From the foregoing, taken in connection with the accompanying drawing, it will be seen that novel and advantageous provision has been made for carrying out the objects of the invention, and while preferences have been disclosed, attention is invited to the possibility of making variations within the scope of the invention as claimed.

I claim:

1. In combination, a portable power driven driiling machine having a casing with a projecting bearing for a rotary shaft which carries a drill, a collar swiveled for rotary movement on said bearing concentric with said shaft, a pressure applying hand lever having near one end spaced and laterally opposed parts forming an open portion through which the drill carrying portion of the shaft projects, flexible connections between diametrically opposite parts of said collar and said opposed parts of the open portion of said lever, a chain having means for anchoring it to a stationary support, and a hook'on said one end of the lever and engaged by said chain.

2. The structure of claim 1 in which said opposed parts of the lever are oppositely bowed with centrally positioned eyes thereon engaged by hooks forming parts of said flexible connections.

3. The structure of claim 1 in which said projecting hearing has in its outer face an annular groove in which said collar is rotatable, said collar comprises opposed semi-circular sections with projecting ends connected by bolts, and in which said flexible connections are anchored to said bolts.

4. A pressure applying attachment for use with a portable power driven drilling machine having a casing with a projecting bearing for a rotary shaft which carries a drill, said bearing having'an annular groove concentric with the shaft, a two section collar rotatable in said groove and having the ends of its sections connected by bolts, a hand lever having oppositely bowed parts forming an open portion near one end of the lever to receive the drill carrying portion of the shaft, said oppositely bowed parts having centrally positioned eyes projecting from one side of the lever, flexible connections fastened at one end to said bolts and having hooks at their other ends engaged with said eyes, a hook on said one end of the lever projecting laterally from its side opposite that carrying said eyes, and a chain with means adjacent one end for anchoring it to a stationary support, the links at the free end of the chain enacting with said last mentioned hook.

5. A pressure applying attachment for use with a portable power driven drilling machine having a casing with a projecting portion having a bearing for a rotary shaft which carries a drill, said attachment comprising a hand lever having near one end a pair of oppositely bowed parts to provide the lever with an open portion to receive the drill carrying portion of the shaft, the central portions of said oppositely bowed parts carrying hook engaging eyes which project from one side of the lever, a hook on said one end of the lever projecting laterally from its side opposite that carrying said eyes, a pair of flexible connections carrying at one end hooks to engage said eyes, the other ends of said flexible connections being adapted to be anchored to said projecting portion of the casing at points diametrically opposite the axis of said shaft, and a chain with means at one end for anchoring it to a stationary support, the links of said chain adjacent its free end coacting with said hook on the lever.

References Cited in the file of this patent UNITED STATES PATENTS 831,607 Elliott Sept. 25, 1906 1,295,700 Cook Feb. 25, 1919 1,684,514 Phillips Sept. 18, 1928 2,217,300 Temple on Oct. 8, 1940 

